Problem displaying website on IE 11

Hi all,

Nice to meet you. First of all, I must state I have been using wordpress for a while for work, but I am not a web developer or something like that, so my knowledge is quite basic. I have been told our website (www.pensar.co.uk) is not correctly displayed on IE11, although it is working well for the rest of browsers. I have no idea of how to proceed. Been searching and reading some of the posts here related to the issue, but I don’t know where to place the codes they say, I think I should need some kind of instructions for dummies.

If someone can help me, that would be much appreciated.

Thanks a lot!

Sara